From the state of the art, with automatic transmissions, using hydraulic pumps (such as vane cell pumps) is known; hydraulic pumps make available the hydraulic pressure required for the operation of the transmission and the required conveying volume of the hydraulic control, by which the cooling and lubrication of the transmission and the actuation of the shifting elements of the transmission can be ensured.
In particular, with automatic transmissions of vehicles, using vane cell pumps, with which the vanes are arranged in slots of the rotor of the pump, is known; the vanes can move freely in the radial direction, are rotated along with the rotor and, through centrifugal force under rotational speed and through pressure oil, are applied, at the rear side of the vane (rear vane support), on the lifting ring of the pump or are pressed onto the inner contour of the lifting ring.
According to the state of the art, vane cell pumps for vehicle transmissions are designed as closed, pre-assembled units that can be tested separately; within the pump, the oil guide is primarily realized through an inserted end plate that is arranged in the bottom area of the vane cell pump. The oil guide features a suction channel and a pressure channel and is designed to be movable in an axial manner, whereas, based on the pressure difference between the two end faces of the end plate, the end plate is slightly pressed against the conveying elements of the pump, by which the axial gap of the pump is compensated for.
According to the state of the art, the end plate features a small thickness, since the pump bottom or housing bottom features a thickness that is not insignificant. This results in the suction channel being designed to be very steep, by which the oil flow is strongly deflected, which disadvantageously results in unfavorable flow conditions.